Process for producing 2-methylnaphthalene

Abstract

The invention provides a process for producing 2-methylnaphthalene by isomerization of 1-methylnaphthalene in which a Y zeolite having a unit cell constant of less than or equal to 24.37 Å (10 -10 m) is used as an isomerization catalyst. Since the isomerization is effected by the use of the inventive heterogeneous solid catalyst which has a long catalyst life, 2-methylnaphthalene is produced from 1-methylnaphthalene efficiently with less cost and handling steps for regeneration or exchange of the catalyst.

What is claimed is: 
     
       1. A process for producing 2-methylnaphthalene by isomerization of 1-methylnaphthalene which comprises using a Y zeolite having a unit cell constant of less than or equal to 24.37 Å (10 -10  m) as an isomerization catalyst and carrying out the isomerization reaction at a temperature in the range of from 350° to 600° C. 
     
     
       2. A process for producing 2-methylnaphthalene by isomerization of 1-methylnaphthalene which comprises using a Y zeolite resulting from a steam treatment and/or an acid treatment as an isomerization catalyst and carrying out the isomerization reaction at a temperature in the range of from 350° to 600° C. 
     
     
       3. The process for producing 2-methylnaphthalene according to claim 1 wherein said Y zeolite having a unit cell constant of less than or equal to 24.37 Å is a Y zeolite resulting from adjustment of its unit cell constant to 24.37 Å or less by a steam treatment at a temperature in the range of from 400° to 1000° C. and/or an acid treatment. 
     
     
       4. The process acording to claim 1, wherein the Y zeolite has a unit cell constant of 24.27 to 24.35 Å. 
     
     
       5. The process according to claim 1, wherein the isomerization reation temperature is in the range of from 400° to 500° C.